Rim joists - where spray foam interior and rigid board exterior meet.
I'm in a climate zone 5 area and have a 3' crawlspace with close to 6" of closed cell spray on the interior of the rim joists. I'm about to re-side possibly with Hardipanels, and insulate from the outside- planning on 2 layers of 1-1/2" of reclaimed polyso, held on with 3/4" furring strips over Tyvec for a rainscreen, well secured , enough to hold the Hardiboard. My intent is to run the siding roughly 1' below the top of the cement block. My question is- where do I end the polyso? I believe layering exterior polyso over top of what is already spray foamed from the interior could create moisture problems in the rim joist area. I'm also curious about what to do with the 3 & 3/4" (poly & furring strips) sticking out past the concrete block foundation. Is there a detail drawing that covers this?
Posted Wed, 07/09/2014 - 13:35
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